1. Field of Art
This invention generally relates to detecting touch events in a touch-sensitive device, especially low power approaches capable of detecting multitouch events.
2. Description of the Related Art
Touch-sensitive displays for interacting with computing devices are becoming more common. A number of different technologies exist for implementing touch-sensitive displays and other touch-sensitive devices. Examples of these techniques include, for example, resistive touch screens, surface acoustic wave touch screens, capacitive touch screens and certain types of optical touch screens.
However, many of these approaches currently suffer from drawbacks. For example, some technologies may function well for small sized displays, as used in many modern mobile phones, but do not scale well to larger screen sizes as in displays used with laptop or even desktop computers. Another drawback for some technologies is their inability or difficulty in handling multitouch events. A multitouch event occurs when multiple touch events occur simultaneously. Another drawback is that technologies may not be able to meet increasing resolution demands.
Another drawback is power consumption. Many touch-sensitive devices are mobile devices, such as mobile phones, laptop computers and tablet computers, where power consumption is an important factor. Furthermore, larger screen size, faster device operation, higher device resolution and multitouch detection are device requirements that can increase power consumption. Power consumption may be a determining factor as to whether a touch-sensitive device is commercially viable.
Thus, there is a need for lower power touch-sensitive systems.